VoicePlus: Remove unused strings

Change-Id: I7e70fc78dd61787b0cb972795cc9d8dee3312161
Automatic translation import

Change-Id: I89e8cf324a292034270146e0b99ee6c83ac0df61
Automatic translation import

Change-Id: I3402025c180e3caca14598f53799e621a5a63b2a
Automatic translation import

Change-Id: I7e583995037669a0367dc7cfe6a566dee10fd447